Description

XULDocument.persist() did not validate the attribute name,
allowing an attacker to inject XML into localstore.rdf that would
be read and acted upon at startup. This could include JavaScript
commands that would be run with the permissions of the browser.

Thunderbird could be vulnerable if JavaScript is
enabled. This is not the default setting and we strongly
discourage users from turning on JavaScript in mail. Thunderbird
is not vulnerable in its default configuration.

Update (13 April 2006)
This flaw has been fixed in Thunderbird 1.5.0.2

Updated versions of Firefox 1.0, Thunderbird 1.0, and the Mozilla Suite 1.7
have been released containing this fix.

Workaround

Upgrade to the fixed versions. Do not enable JavaScript in Thunderbird
or SeaMonkey mail.